Flexible printed circuit board etching high temperature bearing film and preparation method thereof

Abstract

The present invention provides a high-temperature bearing film for etching a flexible printed circuit board, comprising a substrate layer, an acrylic adhesive layer and a release film layer; the acrylic adhesive layer comprises: an acrylic monomer, wherein 70-90 parts by weight of a hard monomer; 10-20 parts by weight of a soft monomer; 1-5 parts by weight of a functional monomer; 30-45 parts by weight of a silicone resin; 5-10 parts by weight of a vinyl silicone oil; 0.8-10 parts by weight of a hydrogen-containing silicone oil; 90-110 parts by weight of a solvent; and 0.1-0.6 parts by weight of an initiator. The present invention also relates to a method for preparing the high-temperature bearing film for etching a flexible printed circuit board, wherein the high-temperature bearing film prepared by the present invention has no residual adhesive and is not prone to liquid seepage.

Description

Technical Field

[0001] The invention relates to the field of high-temperature bearing films, and in particular to a high-temperature bearing film for etching a flexible printed circuit board and a preparation method thereof. Background Art

[0002] Flexible circuit board FPC is a highly reliable and extremely flexible printed circuit board made of polyimide or polyester film as the substrate. It has the advantages of safe performance, small size, light weight, and flexible process. It is widely used in mobile phones, computers, and consumer electronics. FPC high temperature bearing film, also known as FPC process protection film, is mainly used in the production and manufacturing of ultra-thin single-layer RTR ultra-thin flexible circuit boards to improve the product deformation during the production process and improve the convenience and yield of the operation.

[0003] The existing high-temperature carrier film is laminated on the PFC board after high-temperature lamination (180-200°C), and the peeling force increases, which easily leaves residual adhesive on the PFC board; and at high temperatures, the carrier film and FPC are delaminated, bubbles are generated, and liquid seepage is prone to occur.

[0004] Therefore, it is necessary to improve the existing high-temperature bearing film and design a new type of high-temperature bearing film. Summary of the invention

[0005] In order to overcome the shortcomings of the prior art, the first object of the present invention is to provide a high-temperature bearing film for etching a flexible printed circuit board, comprising a substrate layer, an acrylic adhesive layer and a release film layer; the acrylic adhesive layer comprises:

[0006] Acrylic monomer, wherein the hard monomer is 70-90 parts by weight; the soft monomer is 10-20 parts by weight; and the functional monomer is 1-5 parts by weight;

[0007] 30-45 parts by weight of silicone resin;

[0008] 5-10 parts by weight of vinyl silicone oil;

[0009] 0.8-10 parts by weight of hydrogen-containing silicone oil;

[0010] 90-110 parts by weight of solvent;

[0011] Initiator 0.1-0.6 parts by weight.

[0012] Preferably, the hard monomer is at least one of methyl methacrylate, ethyl methacrylate, styrene and acrylonitrile.

[0013] Preferably, the soft monomer is at least one of ethyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, lauryl methacrylate, and n-octyl methacrylate.

[0014] Preferably, the functional monomer is at least one of 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, trifluoroethyl methacrylate, and glycidyl methacrylate.

[0015] Preferably, the acrylic adhesive layer has a thickness of 10-20 um.

[0016] Preferably, the solvent is a mixture of ethyl acetate and toluene.

[0017] Preferably, the initiator is at least one of azobisisobutyronitrile and dibenzoyl peroxide.

[0018] Preferably, the substrate layer has a thickness of 50-75 um.

[0019] Preferably, the release film layer has a thickness of 25-50 um.

[0020] A second object of the present invention is to provide a method for preparing a high-temperature carrier film for etching a flexible printed circuit board as described above, comprising the following steps:

[0021] The weighed raw materials are mixed evenly in a certain proportion to prepare an acrylic adhesive layer, which is then coated on the substrate, baked in an oven at high temperature to dry the solvent, and then placed in an oven for curing after the release film is attached.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides a high-temperature bearing film for etching a flexible printed circuit board, comprising a substrate layer, an acrylic adhesive layer and a release film layer; the acrylic adhesive layer comprises: acrylic monomers, wherein the hard monomer is 70-90 parts by weight; the soft monomer is 10-20 parts by weight; the functional monomer is 1-5 parts by weight; the silicone resin is 30-45 parts by weight; the vinyl silicone oil is 5-10 parts by weight; the hydrogen-containing silicone oil is 0.8-10 parts by weight; the solvent is 90-110 parts by weight; the initiator is 0.1-0.6 parts by weight. The present invention also relates to a method for preparing the high-temperature bearing film for etching a flexible printed circuit board, and the high-temperature bearing film prepared by the present invention has no residual adhesive and is not prone to liquid seepage.

[0023] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention. The specific implementation of the present invention is given in detail by the following embodiments. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0025] The present invention relates to a high-temperature bearing film for etching a flexible printed circuit board, comprising a substrate layer, an acrylic adhesive layer and a release film layer; the acrylic adhesive layer comprises:

[0026] Acrylic monomer, wherein the hard monomer is 70-90 parts by weight; the soft monomer is 10-20 parts by weight; and the functional monomer is 1-5 parts by weight;

[0027] 30-45 parts by weight of silicone resin;

[0028] 5-10 parts by weight of vinyl silicone oil;

[0029] 0.8-10 parts by weight of hydrogen-containing silicone oil;

[0030] 90-110 parts by weight of solvent;

[0031] The initiator is 0.1-0.6 parts by weight; the high-temperature bearing film thus formed is not easily deformed, and does not generate bubbles or liquid seepage at high temperatures.

[0032] The hard monomer may be a common acrylic hard monomer in the prior art; in some embodiments, in order to ensure the quality of the final product, the hard monomer is at least one of methyl methacrylate, ethyl methacrylate, styrene, and acrylonitrile.

[0033] The soft monomer may be a common acrylic soft monomer in the prior art; in some embodiments, in order to ensure the quality of the final product, the soft monomer is at least one of ethyl acrylate, n-butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, lauryl methacrylate, and n-octyl methacrylate.

[0034] The functional monomer may be a common acrylic functional monomer in the prior art; in some embodiments, in order to ensure the quality of the final product, the functional monomer is at least one of 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, trifluoroethyl methacrylate, and glycidyl methacrylate.

[0035] In some embodiments, the acrylic adhesive layer has a thickness of 10-20 um.

[0036] In some embodiments, the solvent is a mixture of ethyl acetate and toluene to improve the overall performance of the product.

[0037] In some embodiments, the initiator is at least one of azobisisobutyronitrile and dibenzoyl peroxide to improve the overall performance of the final product.

[0038] In some embodiments, the substrate layer has a thickness of 50-75 um.

[0039] In some embodiments, the release film layer has a thickness of 25-50 um.

[0040] The present invention also relates to a method for preparing a high-temperature bearing film for etching a flexible printed circuit board, comprising the following steps:

[0041] The weighed raw materials are mixed evenly in a certain proportion to prepare an acrylic adhesive layer, which is then coated on the substrate, baked in an oven at high temperature to dry the solvent, and then placed in an oven for curing after the release film is attached.

[0042] Among them, the preparation method of the acrylic adhesive layer adhesive is as follows: the polymerization temperature during the polymerization of all raw materials is 60-80°C, all solvents are added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an anaerobic environment; the monomer and the initiator are mixed, dripped to the bottom of the reactor, and stirred continuously with a stirring paddle to allow them to react fully, the dripping is completed in 2-3 hours, the reaction is kept warm for 4-6 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0043] Embodiment 1

[0044] The preparation method of the acrylic adhesive layer adhesive is as follows: 70 parts by weight of hard monomer methyl methacrylate; 10 parts by weight of soft monomer ethyl acrylate; 1 part by weight of functional monomer 2-hydroxyethyl acrylate; 30 parts by weight of silicone resin; 5 parts by weight of vinyl silicone oil; 0.8 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 90 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.1 parts by weight of initiator azobisisobutyronitrile are mixed, added dropwise to the bottom of the reactor, and stirred continuously with a stirring paddle to fully react, the dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0045] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0046] Embodiment 2

[0047] The preparation method of the acrylic adhesive layer adhesive is as follows: 90 parts by weight of hard monomer methyl methacrylate; 20 parts by weight of soft monomer ethyl acrylate; 5 parts by weight of functional monomer 2-hydroxyethyl acrylate; 45 parts by weight of silicone resin; 10 parts by weight of vinyl silicone oil; 10 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 110 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.6 parts by weight of initiator azobisisobutyronitrile are mixed, added dropwise to the bottom of the reactor, and stirred continuously with a stirring paddle to fully react, the dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0048] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0049] Embodiment 3

[0050] The preparation method of the acrylic adhesive layer adhesive is as follows: 30 parts by weight of hard monomer methyl methacrylate and 40 parts by weight of styrene; 5 parts by weight of soft monomer ethyl acrylate and 5 parts by weight of lauryl acrylate; 0.5 parts by weight of functional monomer 2-hydroxyethyl acrylate and 0.5 parts by weight of trifluoroethyl methacrylate; 30 parts by weight of silicone resin; 5 parts by weight of vinyl silicone oil; 0.8 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 90 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.1 parts by weight of initiator azobisisobutyronitrile are mixed, added dropwise to the bottom of the reactor, and stirred continuously with a stirring paddle to fully react, the dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0051] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0052] Embodiment 4

[0053] The preparation method of the acrylic adhesive layer adhesive is as follows: 70 parts by weight of hard monomer methyl methacrylate; 10 parts by weight of soft monomer ethyl acrylate; 1 part by weight of functional monomer 2-hydroxyethyl acrylate; 30 parts by weight of silicone resin; 5 parts by weight of vinyl silicone oil; 0.8 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 50 parts by weight of solvent ethyl acetate and 40 parts by weight of toluene are added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.1 parts by weight of initiator azobisisobutyronitrile are mixed, dripped into the bottom of the reactor, and stirred continuously with a stirring paddle to make it fully react, dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0054] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0055] Embodiment 5

[0056] The preparation method of the acrylic adhesive layer adhesive is as follows: 70 parts by weight of hard monomer methyl methacrylate; 10 parts by weight of soft monomer ethyl acrylate; 1 part by weight of functional monomer 2-hydroxyethyl acrylate; 30 parts by weight of silicone resin; 5 parts by weight of vinyl silicone oil; 0.8 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 90 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.05 parts by weight of initiator azobisisobutyronitrile and 0.05 parts by weight of initiator dibenzoyl peroxide are mixed, and added dropwise to the bottom of the reactor, and stirred continuously with a stirring paddle to fully react, the dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0057] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0058] Embodiment 6

[0059] The preparation method of the acrylic adhesive layer adhesive is as follows: 80 parts by weight of hard monomer methyl methacrylate; 15 parts by weight of soft monomer ethyl acrylate; 3 parts by weight of functional monomer 2-hydroxyethyl acrylate; 35 parts by weight of silicone resin; 8 parts by weight of vinyl silicone oil; 5 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 100 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is kept in an oxygen-free environment; the monomer and 0.4 parts by weight of initiator azobisisobutyronitrile are mixed, dripped to the bottom of the reactor, and stirred continuously with a stirring paddle to make it fully react, dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0060] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0061] Comparative Example 1

[0062] The preparation method of the acrylic adhesive layer adhesive is as follows: 60 parts by weight of hard monomer methyl methacrylate; 5 parts by weight of soft monomer ethyl acrylate; 0.5 parts by weight of functional monomer 2-hydroxyethyl acrylate; 20 parts by weight of silicone resin; 2 parts by weight of vinyl silicone oil; 0.4 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 50 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.03 parts by weight of initiator azobisisobutyronitrile are mixed, added dropwise to the bottom of the reactor, and stirred continuously with a stirring paddle to fully react, the dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0063] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0064] Comparative Example 2

[0065] The preparation method of the acrylic adhesive layer adhesive is as follows: 100 parts by weight of hard monomer methyl methacrylate; 30 parts by weight of soft monomer ethyl acrylate; 6 parts by weight of functional monomer 2-hydroxyethyl acrylate; 50 parts by weight of silicone resin; 15 parts by weight of vinyl silicone oil; 15 parts by weight of hydrogen-containing silicone oil; the polymerization temperature during polymerization is 60°C, 150 parts by weight of solvent ethyl acetate is added to the reactor, heated in a water bath and nitrogen is introduced to exhaust the air, and the reaction is carried out in an oxygen-free environment; the monomer and 0.8 parts by weight of initiator azobisisobutyronitrile are mixed, and added dropwise to the bottom of the reactor, and stirred continuously with a stirring paddle to fully react, the dripping is completed in 2 hours, the reaction is kept warm for 4 hours, cooled to room temperature, and the glue is collected to form an adhesive.

[0066] The acrylic adhesive layer is coated on the substrate, and the solvent is dried by high-temperature baking in an oven. After the release film is attached, it is placed in the oven for curing.

[0067] The printed circuit board etching high temperature bearing films prepared in Examples 1 to 6 and Comparative Examples 1 to 2 were tested respectively to obtain the test results shown in Table 1 below.

[0068] Table 1 Test results of different embodiments

[0069]

[0070]

[0071] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the embodiments shown here.

Claims

1. A high-temperature bearing film for etching a flexible printed circuit board, comprising a substrate layer, an acrylic adhesive layer and a release film layer; characterized in that: The acrylic adhesive layer comprises: Acrylic monomer, wherein the hard monomer is 80-90 parts by weight; the soft monomer is 10-20 parts by weight; and the functional monomer is 1-5 parts by weight; 30-45 parts by weight of silicone resin; 5-10 parts by weight of vinyl silicone oil; 0.8-10 parts by weight of hydrogen-containing silicone oil; 90-110 parts by weight of solvent; The initiator is 0.1-0.6 parts by weight; the hard monomer is methyl methacrylate; the soft monomer is ethyl acrylate; and the functional monomer is 2-hydroxyethyl acrylate.

2. The high temperature bearing film for etching a flexible printed circuit board according to claim 1, characterized in that: The thickness of the acrylic adhesive layer is 10-20 um.

3. The high temperature bearing film for etching a flexible printed circuit board according to claim 1, characterized in that: The solvent is a mixture of ethyl acetate and toluene.

4. The high temperature bearing film for etching a flexible printed circuit board according to claim 1, characterized in that: The initiator is at least one of azobisisobutyronitrile and dibenzoyl peroxide.

5. The high temperature bearing film for etching a flexible printed circuit board according to claim 1, characterized in that: The thickness of the substrate layer is 50-75 um.

6. The high temperature bearing film for etching a flexible printed circuit board according to claim 1, characterized in that: The release film layer has a thickness of 25-50 um.

7. A method for preparing a high temperature bearing film for etching a flexible printed circuit board as claimed in claim 1, characterized in that: The following steps are involved: The weighed raw materials are mixed evenly in a certain proportion to prepare an acrylic adhesive layer, which is then coated on the substrate, baked in an oven at high temperature to dry the solvent, and then placed in an oven for curing after the release film is attached.

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